The MGP9 Sportster was a stereo cassette player manufactured by the Sanyo Electric Corporation in China. In the style of a Walkman, it was a portable unit measuring approximately 13 cm × 9.5 cm × 3.5 cm. It required three “AA” sized batteries to provide the power, and a pair of stereo headphones for listening. The Sportster was a very popular line of budget-end alternatives to the Walkman, and Sanyo were able to sell many units worldwide.
They were able to make it cheaply by introducing automation in the manufacturing process. The printed circuit board had a simple circuit resulting in a neat minimalistic design requiring very little soldering by hand. They used plastic wherever possible, however this model has a metal chassis for the tape transport mechanism and pushbutton assembly, and it is approximately a third the size of a conventional one thereby reducing material costs. To simplify the tape transport mechanism, they provided only the fast forward function and not rewind. Much of the mechanism for the fast forward function is the same as that for the play function, which helps to simplify the design. This unit also has an extremely simple and effective auto stop mechanism, which is of course vital for battery-powered applications.
Sound quality wise, the unit uses the Sanyo LA4520 integrated circuit (IC), which was utilised in many stereo cassette players in the 80s. It requires very few external components, and produces that wonderful clear sound that many would recognise today. This is a stereo IC, which contains a pair of preamplifiers to condition the input signals, and a pair of power amplifiers to drive a headphone set. What I love about this IC is the high-performance together with simplicity in the design, which Sanyo were renowned for with their semiconductor technology.
If you can get your hands on a shiny new Sportster, without any wear or scratches, then I am sure you will be pleased with the quality. The original foam-padded 80s headphones that came with this unit were average; however, if you were to use a pair of good quality Sony headphones, then there will be a drastic improvement in sound.
Cost / eBay
This was a mass manufactured product, and due to its low cost many people would have thrown it away. These sometimes appear on eBay in various states, but very rarely in mint condition in its original box. The price can vary from as little as five pounds upwards depending upon the state, and the number of interested people online.
This Article Continues...Sanyo MGP9
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